Perceptual Processes and the Maintenance
of Polymorphism Through Frequency-dependent Predation

Abstract

One of the key challenges of both ecology and evolutionary biology is to understand the mechanisms that maintain diversity. Negative frequency-dependent selection is a powerful mechanism for maintaining variation in the population as well as species diversity in the community. There are a number of studies showing that this type of selection, where individuals of a rare type (i.e. a rare morph or a rare species) experience higher survival than those of more common type(s). However, it is still not clear how frequency-dependent selection operates. Search image formation has been invoked as a possible, proximate explanation. Although the conceptual link between search image and frequency-dependent predation is often assumed in ecological and evolutionary studies, a review of the literature reveals a paucity of evidence demonstrating the occurrence of both in a natural predator-prey system. Advances in the field of psychology strongly support the existence of search image, yet these findings are not fully recognized in the realm of ecology and evolutionary biology, in part, we feel because of confusion and inconsistencies in terminology. Here we try to simplify the language, clarify the advances in the study of frequency-dependent predation and search image, and suggest avenues for future research. We feel that the investigations of both proximate (perceptual mechanisms) and ultimate (pattern of predation) processes are necessary to fully understand the importance of individual behavioural processes for mediating evolutionary and ecological diversity.

Coppinger, R.P. 1969The effect of experience and novelty on avian feeding behaviour with reference to the evolution of warning coloration in butterflies. Part I. Reactions of wild-caught adult blue jays to novel insectsBehaviour354560

Coppinger, R.P. 1970The effect of experience and novelty on avian feeding behaviour with reference to the evolution of warning coloration in butterflies. Part II. Reactions of naïve birds to novel insectsAm. Nat104323335View Article